Boat-hull.



- I L BAZAINE.

A BOAT HULL. APPLICATIONJILED JUNE 3. 1914.

Witnesses;

Patented Mar. 4, 1919.

- way of example,

UNITED STATES -ATENT OFFICE.

LEON BAZAINE, or rssY-nns-moonmmrrx, FRANCE, nssronon T0 soontrn ANONYMEI DES ETABLISSEMENTS nmuron'r, or ISSY-LES-MOULINEAUX, manor.

BOAT-HULL.

Specification of Letters Patent.

Application filed June 3,1914. Serial No. 842,769.

.To all whom it may concern:

Be it known that I, Leon BAZAINE, a citizen of the French Republic, and residing in Issy-les-Moulineaux, France, have invented certain new and useful Improvements in Boat-Hulls, of which the following is a specification.

This invention relates to boat hulls, the construction of which has been more par-.

ticularly studied with a view to its application to hydro-aeroplanes, althoughit can be utilized for building :hulls of boats, hydrolanes, etc. This invention has for its ob- ]ect to combine in the same float the qualities of a sliding or ricocheting hull without I float, instead of being a fiat or curved sur-- face, is constituted by series of partial bottoms arranged at different levels and connected together so as to outline the shape of the hull. Generally speaking, the partial bottoms which maybe considered as having been obtained by sections of a continuous bottom (or of a, portion) of the float and by shifting the panels parallelrto themselves, are arranged in twos relatively to one and the same vertical axis, symmetrically and in one and the same-plane, so that the covers of the edges or ribs constituted by the said oflsets, are flat or curved symmetrical surfaces similar to the shapes of a hull with deep draft; the float thus being limited by walls, the cross-section of which interprets, mathematically speaking by a-polygonal outline,- the outline of a deep draft frame.

The edges or ribs of the offsets produce so to speak water lines of a hull whlch, owing tothe ofl'sets provided in its wall, has the properties of a hydroplane. 4

In the accompanying I Figure 1 shows diagrammatically a section of a float, of common type with rect-an gular section and curved bottom.

drawing given by Fig. 2 shows in dotted lines a typical section of a 'hull with deep draft. The full line shows the hull built according'to this invention by inscribin into the deep draft frame, stepped hollow elements built in accordance with. the cross-section of the float in Fig. 1.

Fig. 3 shows by way of example a construction of a float, half with deep draft, and half hydroplane.

Fig. .4 shows theframes.

Fig.5 is a modified construction, the bottoms of the transverse offsets forming longitudinal offsets for gradual rising and immersion.

Fig. 6 'is a, transverse section showing a modified forward construction having two bottoms each provided with transverse oifsets.

As shown in'Fig. 1 and also in full lines in'Fig.'2, an ordinary float with flat bottom independently of the immerg'ed surfaces with given incidence, or independently of projecting ofi'sets which cause at the high speeds its gradual rise and its gradual and Patented Mar. 4, 1-919.

without shock immersion, has a rectangular section limited by flat or curved surfaces. On the contrary, the cross section of av usual ship of deep draft frame (Fig. 2 in dotted lines) has the shape of a curved triangle or of a V curve, the keel section of which occupies the apex,

According to this invention, and in or- .der to obtain a float which has at the sametime qualities of sliding or ricocheting hulls and of deepdraft parts an ordinary flat or curved bottom a of the float with shallow draft (Fig. 1) has been partly or entirely replaced by. a bottom with stepped surfaces 1) (Fig. 2) forming offsets in crosssection. Bythe termricocheting is meant the phenomena produced when a body is launched upon the surface of the water at an angle to such surface. Owing to the inertia of the molecules of the water, the

body receives therefrom a thrust from below in consequence of the resistance of the water, which thrust has the effect of repulsing the bodylaunched upon the surface of the water and causing the body to skip on the surface of the water rather than to enter and'be immersed.

It is obvious that the elementary bottoms b can be flat or curved andeither parallel to each other or not. They can be entirely orpartly provided with offsets f (Fig. 5). The same applies to their relative dlmensions and to the arrangement of planks a connecting them. i

The transverse ofl'sets can be arranged symmetrically relatively to parallel axes mm, nn, for instance so as to outline adjoiningdeep draft parts which leave between them longitudinal grooves for the discharge of the water.

It will be noted that only a portion of the bottom a of the float can 'be constituted by a combination of surfaces 6 situated at different levels and connected together by planks 0, so that the float can be provided with deep draft parts in front (Figs. 3 and a), and connected at the back to a body having a bottom comprising one or moreflat surfaces. When the bottom of the aft portion or body of the hull comprises a lurality of flat. surfaces, these are I planes of the deep draft action surfaces 6 become smaller. therefore possible, by a suitable choice of perimeters and shapes, to obtain floats, the

sets, there is .a tendency preferab y stepped longitudinally of the ualities of which due to the deep drafts ape can be proportioned as desired to those produced by the sliding or offset surfaces enabling it to come out of water. If owing to the increase of the transverse off- 7 to produce a deep draft .hull, the possibility of navigation in' heavy sea is increased. On the contrary, their decrease, by increasing therespective surface of the bottoms b outlined by. the ofl'sets, makes possible gradual immersion and rising without shocks.

1 What'I claim as my invention and desire to secureby Letters Patent is 1.- A boat hull having a series of offsets, the said ofisets being arranged'in. parallel pairs on .the opposite sides of saidhull and extending longitudinally from the bow aft to an intermediate point of the hull, the remaining. aft portion having a bottom com prising 'aflat surface; ,a dlflere'nt air of oflsetsbeing adantedvto contact the sursaid hull.

face of the water at different speeds of the rovided with a. plurality offsets being symmetri- 2. A boat hull of offsets, the sai cally arranged in pairs on the opposite sides of the said hull, a different pair of offsets serving as the surface of flotation at different speeds of the said hull, said offsets extending longitudinally from the bowaft to an intermediate portion ofthe hull, the remaining aft portion having a bottom com.- prising a flat surface.

3. A boat hull comprising in combination a forward portion provided with' a series of ofisets arranged in symmetrical pairs on the opposite sides of-the said hull,

said forward portion'merging' at an intermediate pointwith a rearward portion, the bottom of which is provided with longitudinalstepped planes. 7

4. A boat hull comprising in combination a forward portion provided with a series of offsets arranged in symmetrical pairs on the opposite sidesof thesaid hull, said forward portion merging at an intermediate point with a rear portion. provided wit? planes stepped longitudinally ofthe hul 5. A boat hull provided with a plurality of ofl'sets arranged in pairs on opposite sides of the hull, a different pair of offsets serving as the surfa ferent speeds of the offsets being divided i tion having its bottom face inclined upwardly and forwardly.-

6.- A boat hull provided with a plurality of flotation at difs id hull,-s'ome ofthe to sections, each secof ofisets arranged in pairs on opposite sides of the hull, a difi'erent pair of offsets serving as .the surface of flotation at different speeds of the said hull, some of the ofi'sets being divided into sections, each section having its bottom face inclined upwardly and forwardly, the forward end of each section being above the rear end of the next adjacent forward section. '7. A boat hull comprising in combination a forward portion'V shaped and provided with a series of transverse ofisets symmetrically arranged on the opposite sides of the said hull, with-a rearward portion the bottom of which is provided with transversesteps.

In testimony whereof I- have signed my name to this specification in. the presence of two subscribing witnesses.

. -Witnesses: Vrcron DUPONT, CnAs. P. PRESSLY.

LEoNmAzAINE. 

